2011 Lab 9

Endocrine and Integumentary

Endocrine

Developing Pituitary - Human Embryo Carnegie stage 22

• Begin by working through Endocrine Development by week 8.
• Then look at the information on each endocrine organ on their related specific page.

Integumentary

Teeth

Fetal Head (12 weeks) lateral

Deciduous teeth

Permanent teeth

• integumentary system specialization by epitheilal/mesenchymal interactions in development and develops with a major contribution from the neural crest.
  • ectoderm of the first pharyngeal arch and neural crest, ectomesenchymal cells.

• week 6 - odontogenesis begins, tooth bud
• 4 morphological stages describing the early tooth development: bud, cap, bell, and terminal differentiation
• 2 sets of teeth: 20 deciduous teeth, 32 permanent teeth
• differential rates of growth, shed at different times over 20 year period
• inductive influence of neural crest with overlying ectoderm
• tooth growth occurs in ossifying jaws

odontoblasts - neural crest-derived mesenchymal cells which differentiate under the influence of the enamel epithelium. Cells secrete predentin, calcifies to form dentin.

ameloblasts - inner enamel epithelium forms pre-ameloblasts differentiate and produce enamel

periodontal ligament - tooth is not anchored directly onto its bony socket (alveolar bone) but held in place by the periodontal ligament (PDL), a specialized connective tissue structure that surrounds the tooth root coating of cementum.

• ligament also act as; a shock absorber, transmitter of chewing forces (from tooth to bone), sensory information (heat, cold, pressure and pain).
  • collagen fiber bundles within the ligament are called "Sharpey's fibres".

Tooth Stages

Tooth development stages

Stage	Image	Human (weeks)
lamina		Week 6
placode		Week 7
bud		Week 8
cap		Week 11
bell		Week 14

Teeth Postnatal

Deciduous teeth

• 6 - 24 months - erupt from gums by pushing toward surface
• 2 years - all deciduous teeth present

Permanent teeth

• 6 years until early adult
• tooth bud lie in gums beneath deciduous teeth
• osteoclasts resorb deciduous teeth roots
• growth affects face shape

Links: Tooth Development

Group Project

• Peer Assessment of your project should now appear on your group discussion page.
• Now you can make changes to your project based upon these reviews and your own concepts of how the project can be improved.
• At this time it is important that you interact with other group members to ensure they agree on the changes you may make.
• You may add additional content to your project.
• Look through the comments made by your peers and assemble a summary of good (positive) and bad (negative) feedback on your project.
  • What are the common features of peer comments?
• Fix those minor problems (formatting, image size, image labelling, text, referencing)
• Are there parts of your project where group members have not worked appropriately or contributed their work?
  • I will initially be discussing this with the groups individually. You will also have the opportunity to "feed back" contribution issues.

Plagiarism

Currently all students originally assigned to each group are listed as equal authors/contributors to their project. If you have not contributed the content you had originally agreed to, nor participated in the group work process, then you should contact the course coordinator immediately and either discuss your contribution or request removal from the group author list. Remember that all student online contributions are recorded by date, time and the actual contributed content. A similar email reminder will be sent to all current students.

Please note the Universities Policy regarding Plagiarism

In particular this example:

"Claiming credit for a proportion of work contributed to a group assessment item that is greater than that actually contributed;"

Academic Misconduct carries penalties. If a student is found guilty of academic misconduct, the penalties include warnings, remedial educative action, being failed in an assignment or excluded from the University for two years.

2011 Projects: Turner Syndrome | DiGeorge Syndrome | Klinefelter's Syndrome | Huntington's Disease | Fragile X Syndrome | Tetralogy of Fallot | Angelman Syndrome | Friedreich's Ataxia | Williams-Beuren Syndrome | Duchenne Muscular Dystrolphy | Cleft Palate and Lip

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SOMS Summer Research Awards

• The Research Support Committee is pleased to announce that it will again be offering Summer Research Awards (SRAs).
• These awards are for undergraduate students carrying out supervised research in SOMS between November 2011 and February 2012.
• Successful students will receive $250 per week for 6 weeks of research. More Information?

Co-ordinator Note

Dr Mark Hill

ANAT2341 Embryology S2 2011 Lecture content is made available on the Monday of the associated lecture week. Some guest lecturers will provide additional handouts or lecture notes. For background information see Embryonic Development and Systems Notes 2011 Timetable | 2011 Students --Mark Hill 06:47, 20 July 2011 (EST)

Course Content 2011

2011 Timetable: | Embryology Introduction | Fertilization | Cell Division/Fertilization | Week 1 and 2 Development | Week 3 Development | Week 1 to 3 | Mesoderm Development | Ectoderm, Early Neural, Neural Crest | Trilaminar Embryo to Early Embryo | Early Vascular Development | Placenta | Vascular and Placenta | Endoderm, Early Gastrointestinal | Respiratory Development | Endoderm and Respiratory | Head Development | Neural Crest Development | Head and Neural Crest | Musculoskeletal Development | Limb Development | Musculoskeletal | Renal Development | Genital | Kidney and Genital | Sensory | Stem Cells | Stem Cells | Endocrine Development | Endocrine | Heart | Integumentary Development | Heart and Integumentary | Fetal | Birth and Revision | Fetal

Glossary Links

Glossary: A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Numbers | Symbols | Term Link

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Cite this page: Hill, M.A. (2024, April 24) Embryology 2011 Lab 9. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/2011_Lab_9

What Links Here?

© Dr Mark Hill 2024, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G